REMOVE RECEIVER STUB FROM BARREL |
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Remove upper Handguard, Gas Piston and Spring then remove lower
Handguard pin |
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Remove Barrel Pin
- Old pin will not be re-used. A new 4mm pin is included with
the compliance parts. |
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Retain the Handguard Pin for later use |
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Use Barrel Arbor to press barrel out of stub.
You may find it necessary to heat the
stub to get your barrel
to break free. In extreme cases it may be necessary to
slit the side or bottom of the
stub to get the stub off of your barrel.
Rapid Fire will be producing hardened arbors. |
PREPARE PARTS
Note: Rapid Fire is
supplying receivers with all holes reamed to size |
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Remove full auto leaf from multi-function spring |
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Multi-function spring with full auto leaf removed |
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Open rear rivet hole to 4mm
- Note: This allows a rivet with the proper size head
be used which will hold
the multi-function spring in place without the need for a
washer under the rivet
head. We are supplying the receiver with a 3mm hole in
case someone wants to use
the original 3mm size rivet. |
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Open rear trigger guard hole to 4mm |
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Rivet set modified to clear multi-function spring leaf |
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The feed ramp didn't get
machined in receivers serial 5 - 120. If you do not
want to return your
receiver to Rapid Fire and do it yourself, then here is a drawing
showing how it should be
cut. |
SET 2 RIVETS |
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Place 3mm rivet from
compliance parts set into front trigger guard
rivet hole |
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Upset rivet using a punch |
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Place 4mm rivet and
multi-function spring in place with stem of rivet
passing thru spring,
receiver, and rear trigger guard hole. Upset rivet with
modified rivet set. |
PREPARE BARREL |
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Install the muzzle extension
of your choice. Remember that the overall length
of the barrel must be
over 16" in length unless you are building a registered SBR.
Extension MUST be welded, blind pinned or
silver soldered in place for your
build to be
compliant with Federal law. |
INSTALL BARREL IN RECEIVER |
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Place gas piston stop in place. I held it in position with a
little axel grease and
you should also smear
some grease on the inside of the receiver barrel bore and
outside surface of the
barrel that will be pressed into the receiver. |
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Start barrel into receiver -
DON'T FORGET TO INSTALL GAS
PISTON STOP |
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Place bolt (with lock)
and "GO"
gauge in receiver and engage bolt locking "ears"
into the receiver's locking recesses. |
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Press barrel into receiver until it "hard" stops on "GO" gauge |
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Cross drill barreled receiver with a 4mm drill using the dimple in receiver as guide |
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Install new 4mm barrel pin which is supplied in your compliance
parts package. |
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Install Ejector from parts kit and stake in place |